Productivity improvements within establishments (e.g., factories, mines, or retail stores) are an important source of aggregate productivity growth. Past research has documented that learning by doing-productivity improvements that occur in concert with production increases-is one source of such...

Economists have shown that large and persistent differences in productivity levels across businesses are ubiquitous. This finding has shaped research agendas in a number of fields, including (but not limited to) macroeconomics, industrial organization, labor, and trade. This paper surveys and...

In markets where spatial competition is important, many models predict that average prices are lower in denser markets (i.e., those with more producers per unit area). Homogeneous-producer models attribute this effect solely to lower optimal markups. However, when producers instead differ in...

Many studies have documented large and persistent productivity differences across producers, even within narrowly defined industries. This paper both extends and departs from the past literature, which focused on technological explanations for these differences, by proposing that demand-side...

There are tremendous across-plant differences in measured productivity levels, even within narrowly defined industries. Most of the literature attempting to explain this heterogeneity has focused on technological (supply-side) factors. However, an industry's demand structure may also influence...

The U.S. has been experiencing a slowdown in measured labor productivity growth since 2004. A number of commentators and researchers have suggested that this slowdown is at least in part illusory, because real output data have failed to capture the new and better products of the past decade. I...

The North Dakota Railroad War of 1905, which pitted a potential entrant (the Soo Line) against an established monopolist incumbent (the Great Northern Railway), offers a lucid empirical example of strategic behavior, and in particular the potential for entry deterrence through product...

Interest in market power has recently surged among economists in many fields, well beyond its traditional home in industrial organization. This has focused empirical attention on markups, the ratios of price to marginal cost in product markets, and markdowns, the ratios of inputs' marginal...

Profit maximizing behavior on the part of firms is a fundamental, but rarely tested, assumption of economics. In this paper, I analyze the decisions made by an MIT trained economist running a company that delivers bagels and donuts. The simplicity and transparency of the business (e.g. marginal...

Over the last thirty years, the use of child safety seats in motor vehicles has increased dramatically, fueled by well publicized information campaigns and legal mandates. In spite of this movement, there is relatively little empirical evidence regarding the efficacy of child safety seats...